1. Field of the Invention
The present invention relates to thermoplastic bags and in particular specially-designed bags having an adhesive closure arrangement. The adhesive is protectively covered until it is desired to close and seal the bag.
The bag comprises a specially-designed pouch formed interiorly of the bag adjacent the open mouth thereof. The cuff is designed to contain one end of an article which is packaged in the bag. The pouch forms a primary, built-in mechanical closure for containing the bag contents. Additionally, a secondary adhesive stripe closure located intermediate the outer pouch wall and the adjacent bag wall provides a tight, integral closure protecting the contents of the bag against intrusion of dust and foreign materials and additionally preserving the freshness of the bag contents. An added advantage of such a bag closure is that since the primary strength of the closure is derived from the interiorly bag pouch, the need for strength in the adhesive seal is not as critical as when only a pressure sensitive adhesive is employed to close and contain the bag contents. This allows for the adhesive which is employed on the bags to be much less aggressive or tacky, thereby facilitating ease of handling and closure manipulation of individual bags.
2. Brief Description of Prior Art
In the past, numerous closure arrangements have been proposed and employed as closure devices for securing plastic bags in a closed condition. Such devices include rubber bands or so-called twist-ties, paper or plastic coated lengths of wire, which are fastened around the gathered and twisted neck of a plastic bag to secure it in closed condition. An obvious disadvantage of such closure devices is that they do not form an integral part of the bag structure and hence, may not in many instances be readily accessible when it is desired to effect closure of the bag. Another closure arrangement for plastic bags which has been employed in the past, without significant commercial success, is the employment of an exposed and unprotected adhesive stripe adjacent the open mouth of such bag structures. Such an arrangement presented many drawbacks. When such bags were packaged within a dispensing carton either in continuous roll form or individually adjacent to one another, the bags had a tendency to stick to one another as well as to exterior objects following dispensing of individual bags from the container, thus making it difficult to use the bags. Also, the adhesives necessarily were relatively non-aggressive in an attempt to alleviate such problems thereby making the closures insecure.